For a number of years, articles of footwear and various items of clothing have been sold with decorative arrays of light sources such as light emitting diodes (LEDs) and/or a loudspeaker capable of producing a sound. This has been particularly popular in children's shoes where the LEDs are arranged to complement other design elements of the shoe such as cartoon characters and the like.
In a typical design of a children's shoe of the type noted above, a module including a plastic housing is placed in a cavity usually formed in the heel area of the shoe. The module mounts a battery, a switch and conventionally an integrated circuit which is connected by wires to LEDs positioned along the outsole, upper or tongue of the shoe. The integrated circuit may also be capable of generating a signal which operates a loudspeaker, typically mounted in the upper or tongue of the shoe in the general area of the LEDs. Systems of this type are shown, for example, in U.S. Pat. Nos. 6,525,487; 6,286,975; 6,012,822; 5,969,479; 5,894,201; 5,812,063 and others.
The integrated circuits employed in modules for children's shoes and other applications are activated by the switch associated with the module. In most designs, the switch is not operated manually but turns on and off in response to the application of an inertial force, pressure or motion. Spring switches such as shown in U.S. Pat. Nos. RE37,220 and 5,909,088 are a popular choice for children's shoes because they are reliable, noiseless and movable from a neutral or off position to a closed or on position in response to walking, running or other motion of the shoe. Pressure switches such as shown in U.S. Pat. Nos. 5,159,768; 5,649,376; 5,855,080 and 5,714,706 are also employed and they operate in response to the application of a weight, e.g. when the child steps onto a surface.
Another type of switch employed in children's shoes and similar applications is a magnetically activated switch such as shown in U.S. Pat. Nos. 5,422,628 and 5,343,190. In these designs, a reed switch and a permanent magnet are mounted within the heel or other area of the shoe. The magnet is movable between a first position where it is spaced from the reed switch and a second position close to the reed switch. A spring normally biases the magnet to the first position, but when motion or an inertial force is applied to the shoe, the magnet overcomes the spring force and moves to the second position where its magnetic field causes the reed switch to close.